The term communication services is meant to mean conventional tele-phony services, telex services, datapack services, datel services, telefax services, videotext services, ISDN-services, mobile telephony services, personal paging services, tele-point-services and general communication between two or more parties. The services recited above are only examples of the services possible and are not intended to limit the scope of the invention.
The term telecommunication network is normally meant to mean the telephone networks, telex networks, circuit connected data networks, picture information transfer networks, private telecommunication networks, radio networks, satellite communication networks and general carriers of the communication services, such as analog transmission, digital transmission, synchronous, multiplex or asynchronous multiplex transmission, ATM, etc., for example. These networks are recited solely by way of example and the invention is not restricted thereto.
The term functionality is meant to mean the ability to perform an operation in a telecommunication network. Examples of functionality include activities and services that can be performed in the telecommunication network. Examples of functionalities include an enquiry to establish a connection path or route between two parties, digit analysis, billing or ticketing. Although not necessary, the functionality may require the availability of dedicated equipment for carrying out the functionality. For instance, if the functionality is to receive tones and to analyze tones, it is necessary to make a tone receiver accessible. Other examples of functionalities include voice-controlled speech information, number translation service, conference calls. Other examples of functionality include the functionalities described in the aforesaid five Swedish patent applications, namely communication in the form of a meeting, personal paging, a method of establishing cooperation with a functionality, meeting connection establishment and communication via intermediaries.
The term connection is meant to mean a circuit-coupled connection or a package-coupled connection. The term to establish a connection is meant to mean in the circuit coupled case that a circuit-coupled connection is established between two hardware terminal devices (or equipment) and in the package coupled case it is meant that a package-coupled connection creates relationships between logic channels on node-interconnecting physical links which. The term to originate or to terminate a connection is meant to mean in the circuit-coupled case to connect originating or terminating equipment to a circuit-coupled connection, and in the package-coupled case to create a session between applications in originating and terminating nodes respectively.
The term user is meant to mean in the following a human user or a computer-based application which utilizes communication services. The application may be achieved with hardware, software and combinations thereof. The word "party" is synonymous to the term user.
The term terminal is meant to mean equipment which is connected to a telecommunication network and which makes the telecommunication services of the network available to a user.
The term port either refers to an access port or to a transit port. An access port is a location where a dedicated terminal is connected to a telecommunication network. An access port is associated with a destination address which goes to an end user. In the case of a standard telephone network, the access ports are located in a telephone station. In the case of the ISDN-network and the mobile telephone network, the access ports are found in a terminal. A transit port is a port in a connection between nodes. A transit port is not associated with any particular destination address, and can be used to establish any selected connection with a final destination. The final destination is given by the destination address. A transit port can transfer a call to another node or can receive a call from another node.
The final destination of a call is a terminal which is identified by a destination identity. The terminal can be present in the same node as a transit port or in some other node to which the call shall be further connected.
One fundamental feature of present-day communication services is that when a party, hereinafter called A, wishes to communicate with another party, hereinafter called B, A sends a call to B, whereupon a connection is established between A and B. The call and the establishment of a connection route is a coupled sequence. By this is meant that the information which A uses in the call, namely information relating to the identification of B's access point in the telecommunication network, causes a connection route, or path, to be established between the parties. This connection can either be circuit-coupled or, in the case of non-continuous transmission methods, a so-called virtual connection, e.g. a package-coupled network, ATM-network (asynchronous transfer mode), etc. Traditionally, a connection is established by establishing a route from an origin to a destination. The connection route through the telecommunication network is controlled by fixed, so-called routing tables which are drawn up when configuring or reconfiguring the network. The routing tables may sometimes permit alternative selections, based on local accessibility information.
The traditional communication network is encumbered with many drawbacks. A first problem concerns handling of the resources of the communication network. Firstly, the communication network is, in itself, a resource which is utilized uneconomically in the traditional method of providing communication services. For example, when party A calls party B, so as to establish a connection through the network from A to B, and party B does not accept the call, the network resources have been used unnecessarily. The same applies when party B is engaged. The case is dependent on the predominant use of present-day networks of channel-associated signalling. This involves establishing a signalling connection, which is then used for speech purposes. With common channel-signalling, which is used primarily in the long-distance network, the signal connection is established with the aid of the data package, or packet, whereas the speech connection, the expensive part of the communication, is not established until B answers. Common channel-signalling is scarcely used in local networks. Secondly, the majority of all established connections do not require party B to act immediately on the information that A will transfer.
In the aforesaid cases, the network resources are either used unnecessarily or are utilized in real time, although it would be possible to utilize the resources at a later time.
Another drawback with the known telecommunication networks is that when party A wishes to communicate with party B, it is necessary for party A to direct the call to the network, since the network must be activated in order to establish the connection with party B. In turn, this requires the network to have knowledge of the access port of party B in the telecommunication network. Furthermore, it is necessary for the telecommunication network to select the connection route between party A and party B. This is achieved with the aid of fixed routing tables. Fixed routing tables, however, are a disadvantage, for instance in the case when a large number of users located within a restricted, local geographic area are called through the telecommunication network at one and the same time, resulting in congestion on certain trunk lines leading to the local area. On such occasions, the node will normally have several unused trunk lines from other geographic areas. The routing tables, however, do not permit these unused trunk lines to be used temporarily for the purpose of relieving the traffic to the local area. By way of example of temporary geographic traffic concentrations can be mentioned, large sporting events of a temporary character, among others.
When seen from the aspect of party B, present-day telecommunication networks are also rigid in structure and slow in redirecting the call to B when B moves from its access port in the telecommunication network. In present-day telephone networks, this problem is solved by service such as "temporary transfer" (diversion) or "redirection". However, if it is necessary for party B to change its access identity permanently, the problem will remain, i.e. that the party who wishes to reach party B must have knowledge of the new access identity. The mobile telephony solves this problem, but at the price of requiring the network to continuously register where B (or B's terminal) can be reached.
The U.S. patent application Ser. No. 515 836 filed on the 27th Apr. 1990 with the title "Apparatus and Method for Directing Calls to Mobile Telephone Subscribers", having the same Applicant as the present application, describes the mobile communication system in which the home exchange of a mobile subscriber is aware of the probable location of the subscriber. Upon receipt of a call, the home exchange requests the exchange where the mobile subscriber is probably located to page the subscriber and to connect the subscriber to a speech channel. This is reported to the home exchange only when the process has been successfully carried out, whereupon the home exchange orders a connection from A to B to be established through the network.
This avoids unnecessary coupling of a call connection from A to the home exchange, as in the case of the earlier used method, and, instead, only one signalling process is effected between A and the home exchange. This signalling process may be carried out, e.g., via CCITT signal system No. 7.
The U.S. patent application Ser. No. 686 600 filed on the 17th Apr. 1991 with the title "A Communications System for Integrating a Paging System with Cellular Radio Telephones" and having the same Applicant as the present application, describes a cellular mobile telephony system having mobile telephones which have pagers built therein. If the mobile telephone is disconnected but the pager is active and an incoming call is made to the mobile telephone, the wide range paging network sends a paging signal which is received by the pager of the mobile telephone, this pager "alerting" the mobile telephone in response to the call and causes the telephone to register itself. The network now steers the call to the mobile telephone by repeating the paging process but now through the cellular mobile telephone network.
The described system includes cooperation between the fixed telephone network, the paging network and the mobile telephone network.
The European Patent Specification No. 140 351 describes a system for increasing the range of cordless telephones. A cordless telephone cooperates via a radio connection with a fixed telephone which has access to the telephone network. The range of the cordless telephone is restricted to the close area around the fixed telephone. In order to increase the range so as to enable a mobile cordless telephone A-MOBIL located within the range of its fixed telephone A-FIX to establish a connection with another mobile cordless telephone B-MOBIL which has its own fixed telephone B-FIX with a range which does not cover the range covered by A-FIX, it is proposed that both of the telephones A-FIX and B-FIX are provided with an auxiliary unit which cooperates, via a switch in the telephone network, with a personal paging system having a range which extends to both A-TEL and B-TEL. The connection from A-MOBIL to B-MOBIL is established by making a call from A-MOBIL and giving the telephone number of B-MOBIL. The fixed telephone A-FIX of the A-MOBIL adds to the B-telephone number an A-FIX-ID which is sent to the exchange and from there to the person paging system. A-FIX then releases its connection with the exchange. The paging signal received by B-MOBIL includes A-FIX-ID. The person served by B-MOBIL can then make a call via another fix-TERMINAL, here called X-FIX, and therewith give A-FIX-ID as the destination. The call passes from B-MOBIL, via X-FIX, via the exchange to the released A-FIX and contact between the parties is established. The communication method described in the patent specification can be described roughly as a conventional A-number transfer system in which the A-number is transferred via the paging network. One drawback with this known system is that A-FIX must release its connection with the exchange in order to be able to receive a call from B-MOBIL. This implies the additional drawback that anyone, whomsoever, is able to call to A-FIX after A-FIX has released its connection with the exchange. Despite A-MOBILE having ordered a call with B-MOBIL, a third party is thus able to call A-MOBIL. The exchange is unable to ascertain which of the incoming calls to A-FIX shall be allowed to pass through. The exchange is ignorant as to whether or not there is a relationship between A-FIX and B-FIX, and neither is the exchange able to handle such a relationship. Another drawback with this system is that all fixed telephones and all mobile telephones and the paging system must be especially designed in order to function together. This involves very high investment costs in order to obtain a system which functions.
There is used in Taiwan a communication system in which when a subscriber A wishes to talk to a person B owning a mobile telephone, subscriber A requests paging of party B and gives his A-number. Party A then releases his connection. The person paging process involves transferring the A-number to the paging apparatus of party B. Party B now calls the A-number on his mobile telephone. A connection is thus established from B to A. A drawback with this method is that the reference, i.e., the A-number, transferred to B points to hardware, i.e., A's telephone apparatus, and it is necessary for A to release his apparatus in order to be able to establish a connection from B to A. Another drawback is that A is not certain that it is B who is calling when A's telephone rings. It is quite possible that some other subscriber rings A before B rings.